Civil engineers at MIT could have a powerful word in the realm of fuel saving. They recently found out by computer simulations that huge amounts of CO2 and fuel could be saved in a year if the road pavements would be stiffer. As much as 3 percent could save 237 million barrels of crude per year.
That amounts to $15.6 billion worth of fuel saved, overall, or 46.5 million metric tons of CO2 not spewed into the air. The study that will be presented this year in the Transportation Research Record, is the first to use math calculations and computer modeling for such a task. Previous versions all tried the experimental approach.
Professor Franz-Josef Ulm and Ph.D Mehdi Akbarian, the study authors, explain that deflections in the pavement are the equivalent to having the go uphill all the time, just like when you walk on sand and your feet get sunk – more energy is being used.
“We’re wasting fuel unnecessarily because pavement design has been based solely on minimizing initial costs more than performance — how well the pavement holds up — when it should also take into account the environmental footprint of pavements based on variations in external conditions,” Akbarian says. “We can now include environmental impacts, pavement performance and — eventually — a cost model to optimize pavement design and obtain the lowest cost and lowest environmental impact with the best structural performance.”
The researchers also say that the initial investments in making existing pavements better by improving the material properties or increasing the thickness of the asphalt layers, switching to a concrete layer or asphalt-concrete composite structures, or changing the thickness or composition of the sublayers of the road will pay for itself relatively quickly because the material would last for longer and would decrease the need for expensive maintenance.